The World Wide Web (“web”) contains a vast amount of information. Search engines assist users in locating desired portions of this information by cataloging web pages. Typically, in response to a user's request, the search engine returns references to documents relevant to the request.
One type of search engine is an image search engine. An image search engine, such as a web-based image search engine, catalogs images from the web. Typically, the image search engine may associate text, such as text that occurs near a particular image, with the image. The text associated with the images may then be searched using conventional key word-based search queries to locate images relevant for the search.
When a user enters a search query for images in an image search engine, the search engine may return hundreds of results (e.g., images or links to images). The large number of potentially relevant results can be daunting for the user. Additionally, because the relevancy of the results may be primarily determined based on text associated with the image, such as text near the image in a web page, the image itself may not match the search or may be of relatively low quality. For example, a search for “Eiffel Tower” may result in some images that include the Eiffel Tower while others may not. Of the images that contain the Eiffel Tower, some may be images taken at odd poses or odd croppings of the Eiffel Tower, or the Eiffel Tower may not be the main focus of the image (for example, the image may primarily be a picture of a person standing at the base of the Eiffel Tower, with the Eiffel Tower only minimally visible in the background).
It is a goal of an image search engine to return relevant and high quality images to the user.